Reduced borehole performance, Kent
A commercial water borehole at a paper mill in Kent was affected by the borehole pumping suspended solids - this had reduced the borehole performance.
About the affected commercial borehole:
406mm diameter to 78m
Cased to 35m with steel casing
Stainless steel screen to base of borehole with 1mm slots
Geology- Folkestone and Hythe beds (Lower Greensand)
The problems with the commercial borehole included:
- The borehole was pumping suspended solids which had reduced its performance.
- CCTV of borehole by EGS indicated that the screens were partially blocked with encrustation from iron bacteria and manganese deposits.
- Turbulent inflow of water towards the base of the borehole.
- Chemistry analysis of the water showed that there were high iron and manganese levels.
How we solved reduced borehole performance
- Mobilise workover rig to site
- Remove existing pumps and riser.
- Clean pump in “acid bath ” to remove any blockages on intakes etc.
- Scrub borehole walls and screen section using purpose built scrubbing tool.
- Backfill a section of the borehole base using clean inert silica gravel and install fabricated concrete “plug” 1.5 long to hold gravel backfill in place.
- Develop borehole by using airlift eductor methodology to minimise potential ingress of air to the system.
- Flush borehole with clearbore product to remove any remaining iron/manganese build up.
- Carry out CCTV survey to assess improvements and install pump on new Certalok uPVC rigid rising main
As a result of the work we carried out at the paper mill in Kent, the client's borehole screens are much cleaner.
Water now runs clear after the borehole pumps are turned on, and the borehole is now back in full supply.
The client has also benefitted from reduced running and maintenance costs due to having a more efficient borehole and cleaner water.
If you're a commercial or domestic client suffering from a reduced water broehole supply, contact us - we will diagnose and solve all your problems.
Other articles of interest
Borehole renovation for a food manufacturer
This case study details a project undertaken by the company to drill a 720mm borehole for a food processing facility to rectify issues left by a former drilling company. We successfully drilled a new borehole to pump 120m3/hr
Refurbishing water boreholes
As well as drilling boreholes and inspecting and maintaining them, the teams at Igne are often called to wells that need refurbishment.